Upright vacuum cleaner having latch mechanism with replaceable stop

ABSTRACT

An upright vacuum cleaner includes a housing having a nozzle assembly and a canister assembly. The nozzle assembly and canister assembly are pivotally connected together. A suction inlet is provided on the nozzle assembly. A dirt collection vessel and a suction generator are both carried on the housing. A latch mechanism secures the canister assembly in an upright or storage position relative to the nozzle assembly. The latch mechanism includes an activator and a replaceable stop.

This application is a continuation of U.S. patent application Ser. No. 11/957,971 filed on 17 Dec. 2007, which claims the benefit of U.S. Provisional Patent Application Ser. No. 60/878,952, filed on Jan. 5, 2007, the full disclosures of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates generally to the floor care equipment field and, more particularly, to an upright vacuum cleaner, equipped with a novel latch mechanism.

BACKGROUND OF THE INVENTION

A vacuum cleaner is an electro-mechanical appliance utilized to effect the dry removal of dust, dirt and other small debris from carpets, rugs, fabrics or other surfaces in domestic, commercial and industrial environments. In order to achieve the desired dirt and dust removal, most vacuum cleaners incorporate a rotary agitator. The rotary agitator is provided to beat dirt and debris from the nap of the carpet or rug while a pressure drop or vacuum is used to force air entrained with this dirt and debris into the nozzle of the vacuum cleaner. The particulate laden air is then drawn into a dirt collection vessel. The air is then drawn through a filter before being directed through the motor of the suction generator to provide cooling. Finally, the air is filtered to remove any fine particles of carbon from the brushes of that motor or other dirt that might remain in the airstream before being exhausted back into the environment.

Upright vacuum cleaners have become evermore popular in recent years. Upright vacuum cleaners typically incorporate a foot or nozzle assembly that is equipped with a suction inlet and a rotary agitator. A canister assembly is pivotably connected to the nozzle assembly. The canister assembly typically houses the suction generator and the dirt collection vessel in the form of a replaceable filter bag or a removable dirt cup. The canister assembly typically includes a control handle. As the vacuum cleaner is manipulated back and forth across the floor with the control handle, the canister assembly pivots with respect to the nozzle assembly so as to allow smooth and efficient operation of the vacuum cleaner.

At any time the canister assembly may be positioned in an upright or storage position. Typically a latch mechanism is provided to secure the canister assembly in the storage position. More specifically, past designs have generally included a cam or stop that is usually molded from a lightweight plastic as part of the vacuum cleaner housing. After extended use this cam can become worn and the latch member then becomes ineffective in securing the canister assembly and handle in the upright storage position.

The present invention addresses and alleviates this problem.

SUMMARY OF THE INVENTION

In accordance with the purposes of the present invention as described herein, an upright vacuum cleaner comprises a housing including a nozzle assembly and a canister assembly. The nozzle assembly and canister assembly are pivotably connected together. In addition, the vacuum cleaner includes a suction inlet carried on the nozzle assembly. Both a dirt collection vessel and a suction generator are carried on the housing. Still further, the upright vacuum cleaner includes a latch mechanism for securing the canister assembly in an upright position relative to the nozzle assembly. That latch mechanism is characterized as including (1) an activator having a first cam surface and (2) a replaceable stop wherein the activator is carried on one of the canister assembly and the nozzle assembly and the replaceable stop is carried on the other of the canister assembly and nozzle assembly.

Typically the activator is carried on the nozzle assembly and the replaceable stop is carried on the canister assembly. In this arrangement the canister assembly includes a receiver and the replaceable stop is held in that receiver. A fastener, such as a screw, is provided for securing the replaceable stop in the receiver. The replaceable stop includes a second cam surface that cooperates with the first cam surface of the activator to perform the latching and unlatching function.

More specifically describing the invention, the nozzle assembly and the canister assembly pivot about a first pivot axis. The activator is pivotably mounted to the nozzle assembly about a second pivot axis that is offset from the first pivot axis. Further, the activator includes a spring biasing the activator into a first position wherein the first cam surface engages the second cam surface to secure the canister assembly in the upright position. In addition, the activator includes a pedal portion whereby the activator is engaged by the operator to pivot the first cam surface about the second pivot axis out of engagement position with the second cam surface so as to release the latch mechanism and allow the canister assembly to pivot relative to the nozzle assembly about the first pivot axis.

Still further, the nozzle assembly may include at least one wall defining an opening having a width W receiving the canister assembly. Further, the at least one wall includes an engineered flex wherein the opening expands to a width of W+F to allow the replaceable stop to pass the first cam surface when the canister assembly is forced from the upright position without disengaging the latch mechanism. This structural arrangement effectively prevents damaging the activator, the replaceable stop and either of the cam surfaces when the activator is handled roughly by the operator and the handle is yanked downward from the storage position without engaging the pedal.

BRIEF DESCRIPTION OF THE DRAWING

The accompanying drawing incorporated in and forming a part of this specification, illustrates several aspects of the present invention, and together with the description serves to explain certain principles of the invention. In the drawing:

FIG. 1 is a partially broken-away perspective view of the floor cleaning apparatus of the present invention;

FIG. 2 is a detailed perspective view of the replaceable stop;

FIG. 3 is a detailed, exploded perspective view showing the canister assembly, receiver, replaceable stop and fastener used to hold the replaceable stop in the receiver of the canister assembly;

FIG. 4 is a view similar to FIG. 3 but illustrating the parts fully assembled;

FIG. 5 is a detailed perspective view of the activator;

FIG. 6 a is a perspective view showing how the cam surfaces of the replaceable stop and activator mesh to secure the canister assembly in the upright storage position;

FIG. 6 b is a view similar to FIG. 6 a but illustrating how the cam surfaces of the activator are pivoted out of the path of the stop to allow the handle and canister assembly to be freely pivoted with respect to the nozzle assembly during operation of the vacuum cleaner;

FIG. 7 a is a top plan view illustrating the engineered flex provided in the wall of the housing of the nozzle assembly;

FIG. 7 b is a schematical view illustrating how the wall of the nozzle assembly with engineered flex allows the replaceable stop and actuator to mesh and lock the handle/canister assembly in the upright, storage position also illustrated in FIG. 1;

FIG. 7 c is a schematical view further illustrating how the engineered flex of the same wall allows the canister assembly receiving opening in the nozzle assembly to expand so that the replaceable stop may slip past the activator when the handle is forced down without first releasing the activator, thereby reducing wear and tear on the latch mechanism; and

FIG. 8 is a schematic view of an alternative embodiment of the invention.

Reference will now be made in detail to the present preferred embodiments of the invention, an example of which is illustrated in the accompanying drawing figures.

DETAILED DESCRIPTION OF THE INVENTION

Reference is now made to FIG. 1, which illustrates the upright vacuum cleaner 10 of the present invention. As illustrated, the vacuum cleaner 10 includes a housing 12 including both a nozzle assembly 14 and a canister assembly 16. The nozzle assembly 14 includes a suction inlet 18 through which air entrained with dirt and debris is drawn into the vacuum cleaner 10. A rotary agitator 20 is mounted to the nozzle assembly 14 and extends across the suction inlet 18.

The canister assembly 16 includes a handle 22 having a handgrip 24. An actuator switch 26 is provided for turning the vacuum cleaner on and off. In addition the canister assembly 16 includes a cavity or receiver 28 for receiving and holding a dirt collection vessel 30 such as a filter bag or dirt cup. A suction generator 32 is mounted in a compartment in the canister assembly 16. During operation, the rotary agitator 20 beats dirt and debris from the nap of the rug or carpet being cleaned. The suction generator 32 draws air entrained with that dirt and debris through the suction inlet 18 into the dirt collection vessel 30. The dirt and debris is trapped in the dirt collection vessel 30 and the now relatively clean air passes through and over the motor of the suction generator 32 to provide cooling before being exhausted through an exhaust port 34 back into the environment.

It should be appreciated that the canister assembly 16 is pivotably connected to the nozzle assembly 14 about a first pivot axis P₁ by means of a trunnion mounting in a manner well known in the art. A latch mechanism, generally designated by reference numeral 40 functions to secure the canister assembly 16 in an upright or storage position relative to the nozzle assembly 14, (note FIG. 1). As illustrated in FIG. 5, the latch mechanism 40 generally includes an activator 42 having a first cam surface 44 and a pedal portion 46. In the illustrated embodiment the activator 42 is pivotably mounted to the nozzle assembly 14 on a pivot pin 47 about a second pivot axis P₂ which is offset from the first pivot axis P₁ (see FIGS. 6 a and 6 b). A spring 48 biases the activator 42 into a first position, which will be described in greater detail below.

The latch mechanism 40 also includes a replaceable stop 50 (see FIG. 2). The replaceable stop 50 is made from a material selected from a group consisting of metal, die cast metal, powder metal, reinforced plastic, fiberglass filled nylon, reinforced polycarbonate and combinations thereof. As illustrated in FIGS. 3 and 4 the replaceable stop 50 is secured in a receiver 52 provided on the canister assembly 16 by means of a fastener such as the screw 54. A second stop 56 is provided on the canister assembly 16. Both the replaceable stop 50 and the second stop 56 extend radially from the hub 58 that functions as the first pivot axis P₁ between the canister assembly 16 and nozzle assembly 14.

As will become apparent from the following description, the replaceable stop 50 functions to lock or secure the canister assembly 14 in the upright storage position while the second stop 56 functions to limit the downward pivoting angle of the canister assembly 16 with respect to the nozzle assembly 14. As oriented, the second stop 56 allows the canister assembly 16 to approach an approximately horizontal position with respect to the nozzle assembly 14 so as to allow an operator to use the vacuum cleaner 10 to clean under a bed, sofa or other furniture. As best illustrated in FIG. 6 a, when in the upright storage position the spring 48 functions to bias the activator 42 so that the first cam surface 44 of the activator engages or meshes with the second cam surface 60 of the replaceable stop 50 thereby positively holding or securing the canister assembly in the upright storage position.

When the operator desires to release the canister assembly 14 and the operating handle 22 from the upright storage position in order to manipulate the vacuum cleaner to and fro across the floor, the operator engages the pedal portion 46. Specifically, the pedal portion 46 of the activator 42 is depressed thereby pivoting the activator about the second pivot axis P₂. This functions to disengage the first cam surface 44 of the activator 42 from the path of the second cam surface 60 of the replaceable stop 50 as the canister assembly 14 is pivoted about the first pivot axis P₁ with respect to the nozzle assembly 12 (see FIG. 6 b). The pedal portion 46 is then released and the canister assembly 14 pivots freely with respect to the nozzle assembly 12 between the replaceable stop 50 defining the upright storage position and the second stop 56 defining the maximum pivotable angle of the canister assembly with respect to the nozzle assembly. This allows the operator to freely manipulate the vacuum cleaner 10 during vacuum cleaner operation. When the operator desires to return the canister assembly 14 and handle 22 to the upright storage position, the operator simply pivots the handle forward. The cam surfaces 44 and 60 engage allowing the replaceable stop 50 to pass past the first cam surface 44 of the activator. The spring 48 then biases the activator into a closed position so that the activator is once again placed in position to secure the canister assembly 14 and handle 22 in the upright storage position.

In accordance with yet another aspect of the present invention, as illustrated in FIGS. 7 a-7 c the nozzle assembly 12 and more specifically, at least one wall 68 of the nozzle assembly 12 defines an opening 70 having a width W that receives the canister assembly 14. More specifically, the opening 70 is in the form of a channel having a bottom 70A and two opposing sides 70B and 70C. During normal operation, when the handle/canister assembly 16 is in the upright or storage position (see FIG. 1), the cam surface 60 of the replaceable stop 50 engages or meshes with the cam surface 44 on the actuator 42 (see FIG. 7 b). This serves to latch and positively hold the handle/canister assembly 16 in the storage position. Significantly, the wall 68 of the nozzle assembly 12 also includes an engineered flex wherein that opening or channel 70 expands to an opening of W+F to allow the replaceable stop 50 to pass the first cam surface 44 of the activator 42 when the canister assembly 12 is forced from the upright position without first disengaging the latch mechanism 40 (see FIG. 7 c).

For example, the opening may have a normal width W of approximately 240 mm and a flexed open width of W+F of approximately 247 mm (see FIG. 7 a). This structural arrangement ensures that the activator 42 and replaceable stop 50 of the latch mechanism 40 function as necessary to secure the canister assembly 14 in the upright storage position under all normal operating conditions. However, when an operator forgets to release the latch mechanism 40 before forcefully ripping the control handle 22 downwardly, the engineered flex ensures that the latch mechanism 40 and particularly the activator 42 and the replaceable stop 50 are protected from excessive wear and tear and are not damaged by such rough handling. This enhances the service life of the latch mechanism 40 and thereby increases the life span over which the vacuum cleaner may be operated and still properly lock with the handle/canister assembly 16 in the upright or storage position.

It should be appreciated that the engineered flex is a product of the resilient plastic material used to produce the wall 68 of the nozzle assembly 12. No separate spring or other mechanical mechanism is required to produce the desired/necessary flex in the wall 68 to accommodate a breakover condition and protect the replaceable stop 50 and activator 42 from excessive wear. Thus, the added expense and reliability issues characteristic of springs and other separate mechanical mechanisms is avoided.

In summary, numerous benefits result from employing the concepts of the present invention. By making the replaceable stop 50 and at least the first cam surface 44 of the activator 42 from strong, low-wear materials, it is possible to significantly enhance the service life of the latch mechanism 40 well beyond that achievable when these structures are molded from standard, lightweight plastic housing materials as in prior art designs. Further, the stop 50 may be replaced if it ever becomes necessary for any reason whereas a stop that is molded as a part of the vacuum cleaner housing cannot. Still further, by engineering a desired flex into the housing of the nozzle assembly the integrity of the latch mechanism 40 is preserved even if the canister assembly is pushed down forcefully and the cam is overridden. Advantageously, the engineered flex is an integral physical characteristic of the wall 68 of the nozzle assembly 12 and not a product of any separate or independent mechanical mechanism such as a spring. This “springless” design is less expensive to produce and maintain.

The foregoing description of the preferred embodiment of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiment was chosen describes the best illustration of the principles of the invention and its practical application to thereby one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as is suited to the particular use contemplated. All such modifications and the variations are within the scope of the invention as determined by the appended claims and interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled. 

1.) An upright vacuum cleaner, comprising: a housing including a nozzle assembly and a canister assembly, said nozzle assembly and said canister assembly being pivotably connected together about a first pivot axis; a suction inlet carried on said nozzle assembly; a dirt collection vessel carried on said housing; a suction generator carried on said housing; and a latch mechanism for securing said canister assembly in an upright position relative to said nozzle assembly, said latch mechanism including (1) an activator having a first cam surface and (2) a replaceable stop wherein said activator is carried on one of said canister assembly and said nozzle assembly and said replaceable stop is carried on the other of said canister assembly and said nozzle assembly; said vacuum cleaner being characterized by said nozzle assembly including at least one wall defining an opening having a width W to receive said canister assembly, said at least one wall further including an engineered flex F wherein said opening expands to a width of W+F to allow said replaceable stop to pass said first cam surface when said canister assembly is forced from said upright position without disengaging said latch mechanism. 2.) The vacuum cleaner of claim 1, wherein said activator is carried on said nozzle assembly and said replaceable stop is carried on said canister assembly. 3.) The vacuum cleaner of claim 2, wherein said canister assembly includes a receiver and said replaceable stop is held in said receiver. 4.) The vacuum cleaner of claim 3, further including a fastener securing said replaceable stop, in said receiver. 5.) The vacuum cleaner of claim 4, wherein said replaceable stop includes a second cam surface. 6.) The vacuum cleaner of claim 1, wherein said activator is pivotably mounted to said nozzle assembly about a second pivot axis offset from said first pivot axis. 7.) The vacuum cleaner of claim 7, wherein said activator includes a spring biasing said activator into a first position wherein said first cam surface engages said second cam surface to secure said canister assembly in said upright position. 8.) The vacuum cleaner of claim 8, wherein said activator includes a pedal portion whereby said activator is engaged to pivot said first cam surface about said second pivot axis out of engagement with said second cam surface so as to allow said canister assembly to pivot relative to said nozzle assembly about said first pivot axis. 9.) The vacuum cleaner of claim 1, wherein said second cam surface of said replaceable stop is made from a material selected from a group consisting of metal, die cast metal, powder metal, reinforced plastic, fiberglass filled nylon, reinforced polycarbonate and combinations thereof. 10.) The vacuum cleaner of claim 10, wherein said first cam surface of said activator is made from a material selected from a group consisting of metal, die cast metal, powder metal, reinforced plastic, fiberglass filled nylon, reinforced polycarbonate and combinations thereof. 11.) The vacuum cleaner of claim 1, wherein said engineered flex of said at least one wall is produced without using a separate spring. 12.) The vacuum cleaner of claim 1, wherein said at least one wall including said engineered flex is void of any separate spring for producing said engineered flex. 13.) The vacuum cleaner of claim 1, wherein said opening defined by said at least one wall is in the form of a channel having a bottom and two opposing sidewalls. 14.) The vacuum cleaner of claim 13, wherein said at least one wall is made from a resilient material providing said engineered flex F. 15.) The vacuum cleaner of claim 14, wherein said at least one wall is void of any separate mechanical mechanism for providing said engineered flex. 